Severus couldn't remember a time when he hadn't believe in magic. It was the only constant in his tumultuous life. Even when his parents' arguments scared him and Severus cowered in his flea-infested bedroom, there were still books full of beguiling spells, dangerous creatures, and smoldering potions. Each tattered book brimming with illuminated passages and hand-drawn illustrations so lifelike that they appeared to climb out of the fragile pages.
But it wasn't until the day he met a tiny girl with hair the color of burnished copper and an easy smile on her freckled face that magic became real for Severus. She had been standing in the overgrown clearing where he'd been hiding from his father's mercurial temper sheer joy shining in her eyes as she made the flower in her hand blossom. Even as a child, Lily Evans, reminded him of the dreamlike fairy princesses in the children's books his father used to read to Severus on the rare days when he wasn't so drunk he stumbled through their ramshackle house before passing out on the broken down sofa. Severus, with a badger's steadfast determination, refused to remember the days when his father was just drunk enough to forget that he loved his son.
Still, magic, never abandoned Severus not even in his blackest moments. The betrayal on Lily's delicate face as he called her a mudblood, in a fit of temper, haunted him. Severus would wrestle a werewolf during the full moon to take back those foolish words, so he could bask in her gentle smiles again. But there was no love anymore in Lily's forest-green eyes only frozen indifference. Back then, the power he'd held over his sneering peers was as heady as the fire whiskey that Malfoy bribed him with when needed a favor from him. He'd been so drunk on power he'd let it cost him the only person who mattered to him.
After losing Lily, Severus retreated into his prized library each book purchased after hours of precise research. He cared for it with the dedication of a niffler chasing a shiny object. Losing himself in the twisted joy that curled inside him whenever he practiced dark magic or brewed potions. Until one Samhain night, beguiling spells and smoldering potions lost their allure.
Severus Snape stopped believing in magic the night Lily Evans died.